ENERGY STORAGE DEVICE

The present disclosure discloses an energy storage device, including a battery pack, a waterproof plug, and a water immersion detection unit. The battery pack includes a housing and a connection terminal. The housing has an opening, and the connection terminal is disposed at the opening. The waterproof plug includes an electrical connection member configured to electrically connect to the connection terminal in response to the waterproof plug covering the opening, and configured to generate a first signal in response to water flowing into the opening. The water immersion detection unit is configured to determine that the water flows into the opening through detecting the first signal. The waterproof plug is small in size and has a simple structure, which is beneficial for reducing production costs of the energy storage device.